Printing plate coating machine



L. B. CORBETT ET AL PRINTING PLATE COATING MACHINE April 7, 1953 V4sheets-sheet 1 Filed OGt. 17, 1950 'I INVENToRs LAWREN( E B. CORBETTPHILIP TATUSKO DONALD R. RATT ATTORNEY April 7, 195s r L. B. CORBETT ETAL PRINTING PLATE COATING MACHINE Filed 001;. 17, 1950 4 Sheets-Sheet 2A INVENTORS LAWRENCE B CORBETT PHILIP TATUSKO DONALD R. PRATT W ATTORNApril '7,

Filed 00T..

L. B. coRBETT ETAL PRINTING PLATE COATING MACHINE Sheets-Sheet 3INVENTORS LAWRENCE B. CORBETT PHiLIP TATUSKO DONALD R. PRATT BY WATTORNEY April 7, 1953 l.. B. coRBET-r ETAL PRINTING PLATE COATINGMACHINE Filed oct. 17, 195o 4 Sheets-Sheet 4 Patented Apr. 7, 1 953 YvUNITED STAEES `JA'EENT GFFICE 2,633,823 i PRNTlNG PLATE COATING MACHINELawrence B. Corbett, Binghamton, Philip Tatusko, Endicott, and DonaldR.Pratt, Apalachin, N. Y., assignors to International Business MachinesCorporation, New York, N.- Y., a corporation of'New York Applicationoctober 17, 1950, serial No. 190,616

s claims. (c1. neuzen) This invention relates to a device for re-inkingthe surface of iiat printing plates and more particularly to means forapplying ink` around the sides of etched recessed surfaces of iiatengraved printing plates.

In the art of photoengraving, a flat sheet of copper, vzinc or othersuitable material is cleaned and coated with a sensitized solution.'This coating is' exposed 'through a prepared negative to obtain thedesired printing or design on the metal. `When themetal plate isdeveloped, the portions of the coating that were exposed through theltransparent areas ofthe negative adhere to the metal plate and form aresistance to the action of etching' acid vwhile 4'the portionsunder theopaque areas of the negative wash away in development and 'these' 'are'the areas that are etched away by the acid.

' After a 'plate "is prepared in this manner, it is etched toa depthgenerally of 001 to .-002 of an L inch. lfth'e 'etching' was 'to becontinued at this point, the acid would begin to undercut the walls orsides of the Vvarious etched characters and produce ragged edges. Toprevent this 'sort of undercutting the sides of the 'etch-ed charactersare 2 does not adhere to the ink is blown ofi. The plate 1s then bakedto harden the ink and powder together. In this manner the fourcumbersome han-d operations are eliminated and a much more effectivejo'b .is done.

In accordance with this it is the main object of the'invention toprovide a device which can be utilized to wipe a relatively uniformrlayer of ink or the like on the vetched side walls in a yflatphotoengraved plate.

It is a further object of the present invention to provide a device forwiping a relatively uniusually built 'up and protected from etching by arather long and tedious 'pov/'dering' process.

This process 'which is in common use today consists of thoroughlydryingthe etched plate and-'then putting "it into a boxconta'inng dragonsblood powder. 'The entire plate is liberally 'cov'- e'redrwith 'this'powder and then the excess is lightly 'brushed oi. 'It is essential thatbrushing be kin one'direc'tion only so as 'to pack the powder againstone side 'of the etched characters. The brushed plate is then heateduntil the powder melts'. When the powder fuses together, 'the 'plate4islduickly lcooled causing the Vpowder to harden and become impervious'to 'acid'. 'This `complete process ismanually repeated in three moredirections "tobuild'up the fou-r sides of the various 'etched charactersand obviously this l'is a long 'and laborious process particularly 'inview-oi the fact thati-t is' required each 'time the depth of thev'etchingV is to be increased.

.l :t is the intention of the 'present invention to facilitate the'abovelmethod now' being 'used 'for strengthening Y'the ibase of etchedcharacters lor the 'like 'on photoengraved printing plates and Ato ldothe'operation in' less 'time and within-ore positiveires'ults. 'We'propose .to employ a device fwhchfwill automatically wipe allay'errofink on the etcllied plate in at least finir directions to completelysurround the oase oi vthi-1i etched char acters Then 'the engraved plateis simply :remov'ed' :from the' (device, an asphaltuim powder risaspri-melee thereon and 'the' excess; powder .which i f forni layerof'inl: or the like on the etched side surfaces 'oi' a fiatphotoengraved plate which inciudcs means Vfor causing said Sink 'tobe'wiped on each edge 'of the etched characters so that the ink will 'bewiped down each side of .the character and be deposited at 'the base.

Vn still further object .is toprovide a device for wiping .a relativelyuniform layer of ink or the like on the fetched side .surfaces of aphotoemgraved plate which includes means for indexing said plate lasVLit is being inked :so that ink inay be wiped against all sides of theetched characters during one operational run of thedevic'e.

Other objects of the invention will be pointed out Ain 'the .followingdescription 'and 'claims and illustrated inthe accompanying drawings,'which disclose, .by way .of example, the principie of the .inventionand the vbest mode, which .has been-contemplated, of .applying thatprinciple'-fv Init'he drawings.:

Fig. '1 is a perspective view showing the general outline ofthe machine.

Fig. 2 'is an end view of 'the inking unit showing the arrangement ofthe inking yroller and the cooperating spreading rollers.

Fig. 3 is a plan View of the machine with the inking unit at the extremeright end in position to commence an hiking run, I l

Fig. 4 is a sectional view 'taken on line 4--11 rof Fig. '3 andvshowsthe eonstru'ction'al details-'of the inking Vunit 'and also aportion of the indexing mechanism. y Y l .5' is a sectional Yview takenon line 5-5 Aoi Fig. B and 'shows constructional details oi theturntable for 'the jphoto'engra'ved plate and the jindexingfmechanismtherefor.

:iandbottom :plate i3 'r'nay be'welded together and to said side plates.The table is supported in the usual manner by four legs I5 which arefastened thereto by the brackets I6 and bolts I1.

Two turntables I6 and I9 are rotatably supported by said stationarytable, said turntables each having a spindle 2U which extends through aball bearing 2I mounted in a bearing block 22 attached to the undersideof the top plate I0. The spindles 20 extend further through apair ofball bearings 23 mounted in bearing blocks 24 attached on the undersideof bottom plate I3. A nut 25 on each spindle 20 is flush against theunderside of ball bearing 23 to act as further support. As shown in Fig.l, the turntable designated I8 has three crossing grooves 26 cut acrossits top surface. Each one of these T- shaped grooves 26 is adapted toreceive a small adjustable block 21 which can be moved along the grooveand which can also be secured against movement by tightening a set screw28 into a lower binding block. The turntable I6 serves as a` support forthe photo-engraved plate 28 `and the adjustable blocks 21 are used tosecure said plate 2S in position on said turntable I8 preparatory toinking. The other turntable I9 functions to support a supply of inkwhich will be taken up by an ink roller unit and spread on the surfaceof the engraved plate 29 in a manner to be described.

Drive mechanism Referring to Fig. 1, a reversing motor 30 is `mountedbelow the stationary table and on a support plate 3| which is attachedto the legs I5. The motor shaft 32 extends 'through a gear box 33 andhas attached on its free end a pulley 34 which through `a belt 35 drivesa pulley 36 and worm shaft 31. The Worm shaft 31 is journalled at eachend of the stationary table in a housing 38 which is attached to theinside of the end plate I2 by means of the bolts 36 (see Fig. 4).

The worm shaft 31 extends through a Worm'. block 4I! attached to theunderside of a plate 4I as-shown in Fig. 4. The plate 4I is the bottom.plate of a carriage unit which is formed by attaching two side plates42 to the bottom plate by means of the bolts 43v as shown in Fig. 5.Theside plates 42 are further supported at the top by means of two rods43a fastened between them. Attached to each side plate 42 by means o fthe bolts 44 are two pairs of rollers 45 adapted to straddle a bar 46fixed, by means of the'bolts 41, along the entire length of each sideplate II.of the stationary table. It will be apparent that as the wormshaft 31 is driven by the motor 36, the carriage unit will be drivenalong the bar `46V by motion imparted to the attached worm block 40. Thedirection of travel of the carriage unit will depend upon the directionof rotation of the worm shaft 31 and accordingly there is" provided ateach end of the stationary table a 'micro-switch 48 so that as thecarriage unit reaches one end of the stationary table one of themicro-switches will be operated by rear plate "42 and closed to reversethe rotation of said motor 3'6 and consequently said worm shaft 31." Asa result the carriage unit will reverse its direction y Inkzngmechanism' As waspreviously mentioned, a supply of'ink is placed on thesurface of turntable I9 which is to be taken up and spread over theetched surfaces of the engraved plate. To perform this function there ismounted in the carriage mechanism an inking roller unit which wipesacross the surfaces of the turntables I8 and I9 as the carriagetraverses back and forth along the stationary table. The inking rollerunit comprises a shaft 49 on which is fixed an inking roller 50 and agear 5I as shown in Fig. 3. Each end of the shaft 49 is journalled in `aball bearing 52 and bearing block 53 which ts into a groove in the sideplates 42 of the carriage mechanism (see Figs. l and 2). The bearingblocks 53 are held down in said grooves by means of bars 54 bolted overthe tops of the side plates 42 by bolts 55 as shown in Fig. 2. A pair ofsprings 56 extending between suitable recesses in the side plates 42 andbearing blocks 53 serve to push said bearing blocks 53 against the setscrews 51. Thus, by adjusting the set screws 51, the inking roller 50may be adjusted vertically with respect to the surfaces of theturntables I8 and I9 to either increase or decrease the amount of inktransferred.

To obtain the best results it has been found that the inking roller 50should exert a wiping action across the surface of the fiat plate sothat the ink wili be scraped along the edges of the etched charactersand forced down along the sides to the base. To accomplish this theinking roller is caused to rotate at a different rate of speed than thelinear speed of the carriage unit. In the present embodiment of theinvention, means are provided for causing the inkng roller 5D to rotateat a faster rate of speed than the linear speed of the carriage unit,but it is to be understood that similar means may be introduced into themachine to cause said inking roller 50 to rotate at a slower rate thanthe linear speed of the carriage unit.

As the inking roller 5I) is carried back and forth by the carriagemechanism it is also caused to revolve by means of a gear rack 58attached to the top plate I 0 of the stationary table and which mesheswith the gear 5I on shaft 49. The circumference of the gear 5I issmaller than the circumference of the inking roller 50 causing saidroller 5U to rotate at a faster rate than the linear speed at which thecarriage mechanism travels. As a result, roller 56 exerts a wipingaction on the surfaces of the turntables I8 and I9 and this is quiteimportant because as roller 5U wipes across the edges of the etchedsurfaces on the engraved plate the ink will be forced down along thesides of the characters and form around the base to prevent futureapplications of etching acid from undercutting the characters.

In order to perform a neat and uniform inking job it is necessary thatthe layer of ink picked up by the roller 50 be spread uniformly aboutthe roller itself and also that any impressions left in the roller, dueto a previous pass over the engraved plate, be removed. Accordinglythere is provided, as shown in Fig. 4, a pair of erasing and spreadingrollers 59 fixed on auxiliary shafts 60 which are journalled at each endin the hinges 6I pivotally mounted on studs 62 fixed to the side plates42. Each hinge 6I is provided with a recess 63 into which extends acompression spring 64. The other ends of the springs 64 extendrintospring retainers 65 which are connected to threaded studs 66 mounted insupport blocks 61 whichY are attached tothe side plates 42 of thecarriage mechanism -by bolts 68. A nut 69 is provided foreach stud 66 so.that the pressure exerted against the hinges 8| by the springs 8lmaybevaried to adjust the pressure exerted on the inking rollerV 50 by thespreadingrollers 59. By adjusting the degreeofl pressure exerted byrollers 59 and regulating the position of the inking roller 50 throughset screws 51, the application of the ink to the surface of the engravedplate may be well controlled.

Indexing mechanism OneV of the features of. the invention is to. providemeans for applying inky to all sides of the'- etched characters on theengraved' plate effectively and' in a minimum amount of timer Toaccomplish this there is provided an indexing mechanism for rotating theturntables |8 and |9 intermittently asthe carriage sweeps back and'forth.

Referring to Figs. 3 and 5;. a flanged ring 1|!l is. mounted on thethreaded bottom portion of: each spindle 20 and is heid fast'l theretoby means of a lock nut 1|.. Loosely mountedv on each. flanged ring 10.for coaction therewith is asleeve 12 which encircles. a series of fournotches 13. spaced 90 apart. around the periphery of said ring 10" asshown in Fig. 3. With the sleeve 12 mounted on said ring 1U. each ofsaid notches 13 is adapted to hold a small steel ball 14. and due to theshape of the. notches 13v a. clutching` action is effected in that. ifthe sleeve 12 is caused to rotate counterclockwise, FigY 3, the balls1'4 will, lodge in the small end of the notchesy and create sui'cientriction between. the sleeve and ring to cause said ring to also rotatecounter-clockwise.. However. if the sleeve 12 should be rotatedin a.clockwise direction the balls 14 will lodge in the large end of: thenotches thereby relieving the friction between the sleeve. and. ringand, allowing said. ring to remain stationary while the sleeve rotatesclockwise.

The drive for the sleeves 12 is takenr from the movement of' thecarriage unit through a pair of rods; 15 and 1.6. Asr seen in Fig. 3,the rod 15 is connected, to sleeve 12' forthe turntable |8 through anadapter 11 and extends towards the right hand end of the machine whereasthe other rod 16;, although connected to sleeve 12 on` the turntable I9"in the same manner through: adapter 18, extends towards the left hand,end of the machine. Attached tothe underside oi. the top Y plate I ofthe stationaryv table are two brackets 1:9 and 88, the bracket 19 being'attached at the right end of the machineV and extending down towards thepath of rod 15, asv shown in Fig. 5, andthe bracket 88 similarlyattached at the left end ofthe machine and extending down towards the.path. of rod 1E. Fixed to the bottom of each bracket 19 and 80 is ablock 8| through which the rod, in alignment therewith,v slidablypasses, as shownv in Fig; 4.

As seen in Figs. 3 and 5 there are xed to the top of plate 4| of the.carriage unit, two blocks 82V and 83. The block. 82 is in alignment withrod 15 and in the path of a disk 84. xed on said rod while the block 83is in alignment with rod 16 and in the path of a' disk 85 xed on saidrod 16. Extending between the disk 84 and the block 8| for rod 15.y and.between disk 85v and the block: 8| for the rod 16 are coil springs 86which tend to force said rods in a direction so that the stop disks 81,mounted on the free ends thereof, will be flush against the sides oftherelated blocks as one isr against. block 8l as shown by' theI posinonof'rod 1s in Fig.. 3..

.To .clarify the operation ofthe indexing mechanismf, assume.- that.vthe carriage unit is et the. extreme right end of the machine. as shown.in Fig. 3. When ther reversing motor 30 is started', the carriage unitwill commence to move toward the left end of. they machine carrying theblocks 82 and 83 with it.v Upon movement of the car-- riage to the left,the block 82 will allow the spring 8&.to force rod. 15 to, the leftuntil stop disk 811s against. the block. 8|. The sleeve 1:2 for turn--table I8; will be drivenv in a clockwise direction. but, aspreviouslyexplained, clockwise movement of sleeve 12 will not clutch ring 10, andso tumtable |:8-: does not index yet.. As thecarriage'unit approachesthe extreme left end of. the machine, the block' 83 will cam disk. 85and rod 18 toward; the: left, causing thevr sleeve 12 to rotate in acounterclockwisey direction. Counterclockwise movementv of the. sleeve12 causes the ring; 10 to be clutched inl and. the turntable |9 will.index in a counterclockwise direction until the carriage stopsv againstmicro-switch 4,8. It follows then that. when the carriage unit reverses`and. moves toward. the right end. of. the machine, the sleeve 1:2. andring 'lo on turntable I9 will be aie-clutched andturntable |9 will notmove whereas block 82 will cam rod 15 to the right causing acounterclockwisev rotation of sleeve 1.2 and ring 10 on the turntable I8to rotate said turntable |8 to index it in a. counterclockwisedirection. until the carriage closes micro-switch 48 at the right end ofthe machine..

In the present embodiment of thev machine, the turntables i8 and I9 willeach be indexed a total of for every two passes of the carriage unit,the inking table I9 being indexed 45 on the. first pass oi the carriagefrom right to left and turntable I8 being indexed 45 on the secondorreturn pass from left to right. The time required to Are-ink. theengraved plate. in 8- diiierent directions is only slightly over 21/2minutes after which it takes about 2. minutes to sprinkle the powder onand 2 more minutes for baking making av total time of approximately 7minutes. This is a great improvement over the hand method of powderingin only 4 directions which requires four separate baking vand coolingoperations. and consumes a total time of. about 20 minutes for eachplate.

In. addition, the presentinvention provides means` for nely adjustingthe amount of ink applied andv for maintaining the application of saidink uniform for as many operations as desired. By the,4 hand` method theuniformity of results is dependent entirely on the skill of theoperator.

While. there have been shown and described. and pointed out thefundamental novel features of the invention as applied to a. singlelmodification, it will be understood that various omissions andVsubstitutions-and changes in the form and details of the deviceillustrated and its operation may be made. by those skilled in the artwithout departing' from the spirit of the invention. It is theintention, therefore, to be limited only as indicated by the scope ofthe following claims.

What is claimedA is: l

l. InV a machine of the class described, a. stationary table, aturntable revolvably mounted on saidI table for holding a supply of ink,a second turntable revolvably mounted on said' table for holding a fiatplate which is to be inked, a movable carriage unit straddling saidstationary table, means to move said carriage unitV back and forth alongsaid stationary table and across' both of said turntables, means undercontrol of said movable carriage for indexing said turntables, aroller'A unit'r fixed on saidl'mova-ble carriage'and having an inkingroller rotatable thereon, and means effective upon movement of saidcarriage unit across both of said turntables for causing said inkingroller to rotate at a different rate than the linear speed of thecarriage unit Whereupon said inking roller will have the eiect of wipingacross the surfaces of said turntables.

2. In a machine of the class described, a, stationary table, a turntablerevolvably mounted on said table for holding a supply of ink, -a secondturntable revolvably mounted on said table for holding a nat plate whichis to be inked, a movable carriage unit straddling said stationarytable, means to move said carriage unit back and forth along saidstationary table and over both of said turntables, means under controlof said movable carriage for indexing said turntables, a roller unit xedon said movable carriage and having an inkl-ng roller rotatable thereon,a gear integral with said inking roller and having a smallercircumference, and a. gear rack on said stationary table and in meshwith said gear to cause the inking roller, upon movement of saidcarriage unit over both of said turntables, to rotate at a faster rateof speed than the linear speed of said carriage.

i 3. In a machine of the class described, a stationary table, aturntable revolvably mounted on said-table for holding a supply of ink,a second turntable revolvably mounted on said table for holding a fiatplate which is to be inked, a movable carriage unit straddling saidstationary table, means to move said carriage unit back and forth alongsaid stationary table and across said turntables, means under control ofsaid movable carriage for indexing said turntables, a roller unit xed onsaid movable carriage and having an inking roller rotatable thereon,means effective upon movement of said carriage unit across saidturntables for causing said inking roller to rotate at a diierent ratethan the linear speed of the carriage unit whereupon said inking rollerwill have the effect of wiping across the surfaces of -said turntables,and means for adjusting said inking roller vertically with respect tosaid turntables to increase or decrease the wiping action.

4. In a machine of the class described, a stationary table, a turntablerevolvably mounted on said table for holding a supply of ink, a secondturntable revolvably mounted on said table for holding a flat vplatewhich is to be inked, a movable carriage unit straddling said stationarytable, means to move said carriage unit back and forth along saidstationary table and over said turntables, means under control of saidmovable carriage for indexing said turntables, a roller unit fixed onsaid movable carriage and having an inking roller rotatable thereon,means effective upon movement of said carriage unit over said turntablesfor causing said inking roller to rotate at a different rate than thelinear speed of the carriage unit whereupon said inking roller will,have the effect of taking ink oi the surface of said first turntable andwiping the ink across the surface of the plate on said second turntable,

and means coacting with the periphery of said "inking roller fordistributing evenly the ink deholding said nat plate which is to beinked, a

movable carriage unit straddling said stationary table, means to movesaid carriage unit back and forth along said stationary table and overboth turntables, a roller unit xed on said movable carriage fortransferring ink from said first turntable to the flat lplate on saidsecond turntable upon movement of vsaid carriage, and indexing means toindex one of said turntables upon movement of said carriage in onedirection and to index the other turntable upon movement of saidcarriage in the opposite direction.

6. In a machine of the class described, a stationary table, a turntablerevolvably mounted on said table for holding a suppiy of ink, a secondturntable revolvablymounted on said table for holding a iiat plate whichis to be inked, a movable carriage unit straddling said stationarytable, means to move said carriage unit back and forth along saidstationary table and across both turntables, a roller unit frxed on saidmovable carriage to transfer ink from said rst turntable to the flatplate on said second turntable upon movement of said carriage, aVuni-directional clutch operatively mounted on each of said turntables, ayieldable connection between each clutch and a bracket attached to saidstationary table, spring operated means normally urging said yieldableconnections and said clutches in arde-clutching direction, and a pair ofcam members attached to said movable carriage and arranged to coa-ctwith said spring operated means to clutch in one of said turntables andindex the opposite direction.

'7. In a device for reinking an etched plate, a main table, an inkvsupply turntable mounted on the top of said table, a plate supportingturntable also mounted on 'the top of said table, an inking roller forwiping over the tops of both said turntables, a frame for holding saidinking roller, spreading rollers rotatably mounted on said frame andcooperating with Vsaid inking roller toV erase impressions therein andspread the ink, means for reciprocating said frame back and forth alongsaid tableand ovei` both of said turntables on each reciprocation, andmeans under control of saidframe for rotating said turntablesalternately by each reciprocation of said frame.

8. In a device for re-inking an etched plate, a turntable, means forsecuring said plate to the top of said turntable, means for rotatablyindexing said turntable step by step, an inking roller, means forapplying ink to said roller, and means for rolling said roller over saidplate with a linear motion, said rolling means including means forturning said inking roller at a dierent speed than the speed of vsaidllinear motion over the plate to wipe 'ink thereon in alternation withthe operation oi said means for rotatably indexing said'plate.

LAWRENCE B. CoRBETr. PHILIP TATUSKO DONALD R. PRATT.

REFERENCES CITED The following references are of record in the i'lle ofthis patent:

UNITED STATES PATENTS Number

